High resolution ("hires") images are required for successful print and digital output. Hi-res captures detail, sharpness and colour range into pixels, which are very small dots of colour that make up the image. Hi-res images have more dots per inch (dpi) than low resolution ("low-res"). When the image is expanded to a larger scale, the dots are stretched. If the resolution is too low (150 dpi or less) detail and sharpness can be lost, resulting in a poor quality photo. Consumer "point and shoot" digital cameras with 7 megapixels and higher are equipped to shoot hires original files. Converting photos from low-res to hires will depend on the original file size and output specifications.
Take the photos you want to be hires and save them to a folder on your computer. Open your photo editing software.
On the software menu bar, there will be an option to check the resolution and size of the photo. (For example, in Photoshop, go to "Image" on the menu screen and scroll down to select "Image size.") A hires photo is 300 dpi and higher. Check that your photos are 300 dpi or higher. If they are not, you can edit the dpi field to make the image 300 dpi.
After converting the image to 300 dpi, check the size of the image in inches. The scale of the image should be at least 100 per cent to the final output. For example, if you are going to make a 4 x 6 print, the image should be 4 inches by 6 inches at 300 dpi.
Save the new converted hires file into another folder called "hires." Repeat the steps for all the photos. When you are finished, you can either print the photos on your printer or find out how a third-party service needs the files for printing.